Pitman.



J. DAIN.

PITMAN. Arrmouxox rrLnn ooi-.19,1oo1.

Patented Apr. 27, 1909.

PATENT OFFICE.

JOSEPH DAIN, OF OTTUMWA, IOWA.

PITMAN.

To all whom 'Lt 'may concern:

Be it known that I, JOSEPH DAIN, a citizen of the United States, residing at Ottumwa, in the county of Wapello and State of Iowa, have invented certain new and useful Improvements in Pitnien, of which the following is a specification, reference being had to the accompanying drawings.

My, invention relates to pitmen, and particularly to pitmen adapted to driving the knife of a mowing machine or similar machine',` and its principal object is to provide a new `and im roved mechanism by which the pitman'can e adjusted so that the stroke of the knives will register pro erly with the ledger-plates on theguards. lln other` words, by which the distance between the wrist pin Aon the crank-wheel and the connecting-head on the knife can be shortened or lengthened as may be necessary in order to cause the centers of the sections of the knife to stroke to the center of the ledger-plates on the guards.

In use a mowing or similar machine is apt to wear in its various joints so that the cutterbar is apt to lag somewhat, thereby affecting the register. In addition to this, the pitmen seem to vary slightly in length, and it has been found necessary to provide means for a proper adjustment of the pitmen to secure the proper registry whenever the knife sec.. tions fail to stroke to the centers of the ledger plates on the guard. This registry isnecessa in order to insure its cutting freely and easily and to leave even stubble. It has been usual, therefore, to make the pitman'of iron, steel or other similar metal and to screwthread it at one end or the other so that it -might be screwed farther into or out of the wrist-pin box or knife-head connection in order that the distance between the wrist-pin on the crank wheel and the connecting-head might be shortened or lengthened to secure proper registry. Owing, however, to the pitmen travelin lr at high speed and making two full stops andastarts at each revolution of the crank-wheel crystallization of the metal is apt to occurwhich causes frequent breakings of the pitmen-rod, causing annoying delays and time and expense in repairing. As a result of trials and experiments it has been demonstratedthat a pitman made of suitable wood is better because the crystallization and consequent breaka e is thereby eliminated. The weight of t e pitman is also reduced, lessening wear and tear on the Wrist-pin as Specification of Letters Patent.r

Application filed October 19, 1907.

Patented April 27, 1909.

Serial No. 398,207.

well as pressure on the knife, and in addition to that it is not so easily sprung or bent,

which often happens to the iron pitman, causing a loss of considerable power and undue friction. The disadvantage, however, of the wood-pitman was that it has not been practical to provide it with suitable means of adjustment. The straps or clamps which fasten the pitman at one end to the journal box of the wrist-pin and at the other end to the knife-head have been usually fastened to the wood with rivets or bolts, and it has been attempted to correct the register by making new holes in the Wood so as to set the straps or jaws in different positions. This, however, is objectionable because it is very seldom necessary to make the new holes more than a quarter of an inch away from the old holes. This is not a sufiicient distance from the old holes to prevent the breaking of the rivets or bolts throu h to the old holes under the thrust and pull o the rapid motion given to the pitman.

It is the object of my invention, therefore, to provide a new and improved means for ad'ustin the itman to overcome the difficuities a ove escribed, by means of which a wooden pitman may be used and readily and easily ad'usted.

To that en ,'therefore, my invention consists in providing for the pitman an eccentric bearing-box in which the wrist-pin of the crank shaft is journaled and which is mounted in a box strap so that it may be turned therein and locked in any desired position. I accomplish this object as illustrated in the drawings and hereinafter described.

That which I believe to be new is set forth in the claims.

In the drawings,-Figure 1 is a to i or plan view of a part of the knife-bar an( its supports, the pitman and the crank-Wheel of a mower, showing the pitman-rod broken away; Fig. 2 is an enlarged detail, being a side view of my improved bearing-box and means for' securing 1t to the pitman Fig. l3 is an enlarged detail, being a top or plan view of the bearing-box and box-strap; Fig. 4 is an enlarged detail, being a vertical section on line 4 4 of Fig. 3.

Referring to the drawings,5 indicates the crank-wheel or disk of a mowenifsecured to the shaft 6 of a mower. l

7 indicates the knife-bar provided with knife-sections 8, which is slidingly mounted in bearings 9-9 and moves in the usual man- 'machina or ner over the ledger-platesulO of the usual ing machine of any well-known form and descriptionin the well-known way, it is believed that it is not necessary to show the other parts of the mowing machine or similar to further describe the parts in question.

11 indicates a pitmm, which is preferably made of Wood.

12 indicates the knife-head, which is riveted or bolted to the knife 7 and is provided With the usual ball 13 which engages with the sockets 14 to form a universal bearing. The sockets 14 are formed upon the ends of the stra s 15, whichare bolted or riveted to the e end of the pitman 11 and are adjusted by means of a bolt 16.

17 indicates a strap or split-ring whose opening is circular in sectionand which is provided with two projections 18-19 having tapered openings 20.

21 indicates straps, which are bolted, or otherwise secured, to the crank end of the pitman 11 and project beyond the end of the same. The dprojecting ends of the straps 21 are provide upon their under or opposing surfaces with tapered bearings 22 which are to fit revolubly within the tapered adapted openings 20 of the projections 18-19 of the split-rin 17 and are secured in place by means o a bolt 23, by meansof which they ma be suitably tightened in position so as to ock the split-ring or box-strap upon the eccentric bearing-box hereinafter described. One edge of the split-ring is provided with a number of notches 24 to engage the lugs on the eccentric bearing-box hereinafter described.

v25 indicates a bearing-box circular in section and adapted to revolubly split-ring or strap-bearing17. The bearingboX 25 is supplied with an eccentric opening 26 in which the wrist-pin 27 of the crank Wheel 5 is journaled.

28--28 indicate lugs, which are preferably two in number and located diametrically opposite each other formed in the outer surface of the bearing-box 25 and adapted to engage the notches 24 of the split-ring 17. The caring-box 25, as is best shown in Fig. 3, tapers slightly from the opposite end toward the lugs 28 and the interior surface of the split-ring or strap-bearing 17 is vcorrespondin ly tapered in order to insure the rigid ho ding of the bearingbox with only a slight clamping of the split-ring by the bolt 23, because the natural tendency will be fr the lugs owing to the taper to work deeper taper.

fit within the smaller end of said tapered portions,

into engagement with the notches and any tendency forthe box to work in the opposite direct ion will be counteracted by the As is best shown in dotted lines in Fig. 3 and in'section in F ig. 4, the surface of the bearing-box 26, which lies within the split-ring, is provided with a groove 31 which extends around the greater part of the periphery of the bearing-box and widens and deepens from its ends toward the middle, constituting an oil chamber by means of which the parts may be oiled.

29 indicates an opening in the split-ring through which oil, or other lubricant, may be introduced into the groove 28, and 3() indicates openings leading into the eccentric opening 26 of the bearin-box 25, by means of which oil may pass t rough to pro erly lubricate the wrist-pin in the eccentric ing-box.

It will be obvious from the above description that by loosening the bolt 23 the pressure of the split-ring or box-strap 17 upon the eccentric bearing-box may be loosened, and said box-strap pushed toward the crankwheel and thus disenga e the lugs 28 from the openings 24. By t en turning the eccentric bearing-box 25 in the split-ring 17 the distance between the wristin 27 and the knife-head 12 may be ,suita ly lengthened or shortened and adjusted to cause the proper register of the knife sections with the edger-plates of the guards. When this adjustment is secured, the split-rin 17 is again slid down the taper so that the ugs 2 8 may engage with others of the notches 24 and locked in position by the tightening on the bolt 23.

That which I claim as my invention, and desire to secure by Letters Patent, is,-

1. The combination with an eccentric having a tapered surface, of a bearing strap having a correspondingly tapered opening, said eccentric and strap being'provided wit a lug and notches adapted to interengage to lock said eccentric against rotation in said strap in any desired position.

2. The combination with a plitman, and va wrist pin, of a bearing sleeve avin aneccentric opening for said wrist pin an having its bearing surface tapered, a strapwhaving its opening correspondingly tapered,v said eccentric and strap being provided, neai` the with lugs and notches adapted to interengage and lock said eccentric in any desired operative position in'said strap.

3. The combination with a itman, and a Wrist pin, of a bearing-sleeve havin an eccentric opening for said wrist pin an having its bearing surface tapered, a strap having its opening correspondingly tapered and having a plurality of notches on its edge at the smaller end of said tapered opening, and lugs on said eccentric near the smaller portion 0l said ta ered surface adapted to enand having on its peri hery extending cir- 1.'-

gage said notc les.

4. rPhe combination with a box-strap having its opening slightly tapered and having notches upon its periphery at the sinaller side ol' its tapered opening, of a journal bearing correspondingly tapered and revolubly mounted 1n said box-strap and having an eccentric opening adapted to receive a wrist- 1 pin, lugs on said journal bearing adapted t0 engage said notches, and means for clamping said box-strap on said journal bearing.

5. 'lhe combination with an eccentric having an opening adapted to receive a wrist pin cuinferentially around t 1e greater' portion 0l the saine an oil groove gradually widening and deepening i'roni each ol' its ends toward the center' and having oil openings connecting said oil groove with said wrist pin openj ing, oll a bearing strap provided with an oil o )ening communicating `l'roin its exterior to the groove on said eccentric.

JOSEPH DALY.

Witnesses:

MERRILL (.3. GILMonE, (i. 1,)UFFIELD. 

